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E. B. Sonin - One of the best experts on this subject based on the ideXlab platform.
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Comment on "Amplitude of Waves in the Kelvin-Wave cascade"
JETP Letters, 2020Co-Authors: E. B. SoninAbstract:In the recently published preprint arXiv:200.02610 Eltsov and L'vov calculated the amplitudes of Waves in the Kelvin-Wave cascades. This returns us to the rather old, but still unresolved dispute on the role of the tilt symmetry and the locality in the Kelvin-Wave cascade. The estimations by Eltsov and L'vov show that the possible nonlocality of the energy flux in the Kelvin-Wave cascade has no essential effect on the Kelvin-Wave cascade in the 3D vortex tangle.
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Reply to ``Comment on `Symmetry of Kelvin-Wave dynamics and the Kelvin-Wave cascade in the T=0 superfluid turbulence' ''
Physical Review B, 2012Co-Authors: E. B. SoninAbstract:I discuss the Comment by L'vov and Nazarenko (arXiv:1208.4593) aiming at refutation of my perviously published criticism of their mechanism of the Kelvin-Wave cascade. It is important that in their Comment L'vov and Nazarenko admitted that the Hamiltonian, from which they derived their mechanism, is not tilt-invariant. This provides full ammunition to their critics, who believe that their mechanism is in conflict with tilt symmetry of the Kelvin-Wave dynamics in an isotropic space.
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reply to comment on symmetry of Kelvin Wave dynamics and the Kelvin Wave cascade in the t 0 superfluid turbulence
Physical Review B, 2012Co-Authors: E. B. SoninAbstract:I discuss the Comment by L'vov and Nazarenko (arXiv:1208.4593) aiming at refutation of my perviously published criticism of their mechanism of the Kelvin-Wave cascade. It is important that in their Comment L'vov and Nazarenko admitted that the Hamiltonian, from which they derived their mechanism, is not tilt-invariant. This provides full ammunition to their critics, who believe that their mechanism is in conflict with tilt symmetry of the Kelvin-Wave dynamics in an isotropic space.
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Symmetry of Kelvin-Wave dynamics and the Kelvin-Wave cascade in the T = 0 superfluid turbulence
Physical Review B, 2012Co-Authors: E. B. SoninAbstract:Racah Institute of Physics, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel(Dated: January 17, 2012)The article considers implications of tilt symmetry (symmetry with respect to tilting of the co-ordinate axis with respect to which vortex motion is studied) in the non-linear dynamics of KelvinWaves. The conclusion is that although the spectrum of Kelvin Wave is not tilt-invariant, this doesnot compromise tilt invariance of the Kelvin-Wave cascade vividly argued now in the theory ofsuperfluid turbulence. The article investigates the effect of strong kelvon interaction on the power-law exponent for the Kelvin-Wave cascade and suggests a simple picture of the crossover from theclassical Kolmogorov cascade to the quantum Kelvin-Wave cascade, which does not encounter withmismatch of the energy distributions at the crossover and does not require a broad intermediateinterval for realization of the crossover.
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symmetry of Kelvin Wave dynamics and the Kelvin Wave cascade in the t 0 superfluid turbulence
Physical Review B, 2012Co-Authors: E. B. SoninAbstract:Racah Institute of Physics, Hebrew University of Jerusalem, Givat Ram, Jerusalem 91904, Israel(Dated: January 17, 2012)The article considers implications of tilt symmetry (symmetry with respect to tilting of the co-ordinate axis with respect to which vortex motion is studied) in the non-linear dynamics of KelvinWaves. The conclusion is that although the spectrum of Kelvin Wave is not tilt-invariant, this doesnot compromise tilt invariance of the Kelvin-Wave cascade vividly argued now in the theory ofsuperfluid turbulence. The article investigates the effect of strong kelvon interaction on the power-law exponent for the Kelvin-Wave cascade and suggests a simple picture of the crossover from theclassical Kolmogorov cascade to the quantum Kelvin-Wave cascade, which does not encounter withmismatch of the energy distributions at the crossover and does not require a broad intermediateinterval for realization of the crossover.
Boris Svistunov - One of the best experts on this subject based on the ideXlab platform.
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kolmogorov and Kelvin Wave cascades of superfluid turbulence at t 0 what lies between
Physical Review B, 2008Co-Authors: Evgeny Kozik, Boris SvistunovAbstract:As long as vorticity quantization remains irrelevant for long-Wave physics, superfluid turbulence supports a regime macroscopically identical to the Kolmogorov cascade of a normal liquid. At high enough Wave numbers, the energy flux in Wavelength space is carried by individual Kelvin-Wave cascades on separate vortex lines. We analyze the transformation of the Kolmogorov cascade into the Kelvin-Wave cascade, revealing a chain of three distinct intermediate cascades supported by local-induction motion of the vortex lines and distinguished by specific reconnection mechanisms. The most prominent qualitative feature predicted is unavoidable production of vortex rings of a characteristic size.
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scale separation scheme for simulating superfluid turbulence Kelvin Wave cascade
Physical Review Letters, 2005Co-Authors: Evgeny Kozik, Boris SvistunovAbstract:A Kolmogorov-type cascade of Kelvin Waves-the distortion Waves on vortex lines-plays a key part in the relaxation of superfluid turbulence at low temperatures. We propose an efficient numeric scheme for simulating the Kelvin-Wave cascade on a single vortex line. This idea is likely to be generalizable for a full-scale simulation of different regimes of superfluid turbulence. With the new scheme, we are able to unambiguously resolve the cascade spectrum exponent, and thus to settle the controversy between recent simulations of Vinen, Tsubota, and Mitani [Phys. Rev. Lett. 91, 135301 (2003)]] and recently developed analytic theory [Phys. Rev. Lett. 92, 035301 (2004)]].
Sergey Nazarenko - One of the best experts on this subject based on the ideXlab platform.
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Comment on ``Symmetry of Kelvin-Wave dynamics and the Kelvin-Wave cascade in the T=0 superfluid turbulence''
Physical Review B, 2012Co-Authors: Victor S. L'vov, Sergey NazarenkoAbstract:We comment on the paper by Sonin [Phys. Rev. B 85, 104516 (2012)] with most statements of which we disagree. We use this option to shed light on some important issues of a theory of Kelvin-Wave turbulence, touched on in Sonin's paper, in particular, on the relation between the Vinen spectrum of strong and the L'vov-Nazarenko spectrum of weak turbulence of Kelvin Waves. We also discuss the role of explicit calculation of the Kelvin-Wave interaction Hamiltonian and ``symmetry arguments'' that have to resolve a contradiction between the Kozik-Svistunov and the L'vov-Nazarenko spectrum of weak turbulence of Kelvin Waves.
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On role of symmetries in Kelvin Wave turbulence
Journal of Low Temperature Physics, 2010Co-Authors: Vladimir Lebedev, Victor S. L'vov, Sergey NazarenkoAbstract:E.V. Kozik and B.V. Svistunov (KS) paper "Symmetries and Interaction Coefficients of Kelvin Waves", arXiv:1006.1789v1, [cond-mat.other] 9 Jun 2010, contains a comment on paper "Symmetries and Interaction coefficients of Kelvin Waves", V. V. Lebedev and V. S. L'vov, arXiv:1005.4575, 25 May 2010. It relies mainly on the KS text "Geometric Symmetries in Superfluid Vortex Dynamics}", arXiv:1006.0506v1 [cond-mat.other] 2 Jun 2010. The main claim of KS is that a symmetry argument prevents linear in Wavenumber infrared asymptotics of the interaction vertex and thereby implies locality of the Kelvin Wave spectrum previously obtained by these authors. In the present note we reply to their arguments. We conclude that there is neither proof of locality nor any refutation of the possibility of linear asymptotic behavior of interaction vertices in the texts of KS.
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modeling Kelvin Wave cascades in superfluid helium
arXiv: Chaotic Dynamics, 2009Co-Authors: G Boffetta, Jason Laurie, A Celani, D Dezzani, Sergey NazarenkoAbstract:We study two different types of simplified models for Kelvin Wave turbulence on quantized vortex lines in superfluids near zero temperature. Our first model is obtained from a truncated expansion of the Local Induction Approximation (Truncated-LIA) and it is shown to possess the same scalings and the essential behaviour as the full Biot-Savart model, being much simpler than the latter and, therefore, more amenable to theoretical and numerical investigations. The Truncated-LIA model supports six-Wave interactions and dual cascades, which are clearly demonstrated via the direct numerical simulation of this model in the present paper. In particular, our simulations confirm presence of the weak turbulence regime and the theoretically predicted spectra for the direct energy cascade and the inverse Wave action cascade. The second type of model we study, the Differential Approximation Model (DAM), takes a further drastic simplification by assuming locality of interactions in $k$-space via a differential closure that preserves the main scalings of the Kelvin Wave dynamics. DAMs are even more amenable to study and they form a useful tool by providing simple analytical solutions in the cases when extra physical effects are present, e.g. forcing by reconnections, friction dissipation and phonon radiation. We study these models numerically and test their theoretical predictions, in particular the formation of the stationary spectra, and the closeness of the numerics for the higher-order DAM to the analytical predictions for the lower-order DAM .
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Kelvin Wave turbulence generated by vortex reconnections
Jetp Letters, 2007Co-Authors: Sergey NazarenkoAbstract:Reconnections of quantum vortex filaments create sharp bends, which degenerate into propagating Kelvin Waves. These Waves cascade their energy down-scale and their Wave action up-scale via weakly nonlinear interactions, and this is the main mechanism of turbulence at scales less than the inter-vortex distance. In the case of an idealized forcing concentrated around a single scale k 0, the turbulence spectrum exponent has a pure direct cascade form −17/5 at scales k > k 0 [B. V. Svistunov, Phys. Rev. B 52, 3647 (1995)] and a pure inverse cascade form −3 at k < k 0 (V. Lebedev, private communication). However, forcing produced by the reconnections contains a broad range of Fourier modes. What scaling should one expect in this case? An answer to this question has been obtained using the differential model for the Kelvin Wave turbulence introduced in [S. Nazarenko, JETP Lett. 83, 198 (2005)]. The main result is that the direct cascade scaling dominates; i.e., the reconnection forcing is more or less equivalent to a low-frequency forcing.
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Kelvin Wave turbulence generated by vortex reconnections
arXiv: Other Condensed Matter, 2006Co-Authors: Sergey NazarenkoAbstract:Reconnections of quantum vortex filaments create sharp bends which degenerate into propagating Kelvin Waves. These Waves cascade their energy down-scale and their Waveaction up-scale via weakly nonlinear interactions, and this is the main mechanism of turbulence at the scales less than the inter-vortex distance. In case of an idealised forcing concentrated around a single scale k0, the turbulence spectrum exponent has a pure direct cascade form -17/5 at scales k>k0 and a pure inverse cascade form -3 at k
Kelvin Wave turbulence. The main result is that the direct cascade scaling dominates, i.e. the reconnection forcing is more or less equivalent to a low-frequency forcing.
Itamar Procaccia - One of the best experts on this subject based on the ideXlab platform.
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Temperature suppression of Kelvin-Wave turbulence in superfluids
EPL (Europhysics Letters), 2012Co-Authors: Laurent Boue, Victor S. L'vov, Itamar ProcacciaAbstract:Kelvin Waves propagating on quantum vortices play a crucial role in the phenomenology of energy dissipation of superfluid turbulence. Previous theoretical studies have consistently focused on the zero-temperature limit of the statistical physics of Kelvin-Wave turbulence. In this letter, we go beyond this athermal limit by introducing a small but finite temperature in the form of non-zero mutual friction dissipative force; A situation regularly encountered in actual experiments of superfluid turbulence. In this case we show that there exists a new typical length-scale separating a quasi-inertial range of Kelvin Wave turbulence from a far dissipation range. The letter culminates with analytical predictions for the energy spectrum of the Kelvin-Wave turbulence in both of these regimes.
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exact solution for the energy spectrum of Kelvin Wave turbulence in superfluids
Physical Review B, 2011Co-Authors: Laurent Boue, Ratul Dasgupta, Jason Laurie, Victor S Lvov, S Nazarenko, Itamar ProcacciaAbstract:We study the statistical and dynamical behavior of turbulent Kelvin Waves propagating on quantized vortices in superfluids and address the controversy concerning the energy spectrum that is associated with these excitations. Finding the correct energy spectrum is important because Kelvin Waves play a major role in the dissipation of energy in superfluid turbulence at near-zero temperatures. In this paper, we show analytically that the solution proposed by [L’vov and Nazarenko, JETP Lett. 91, 428 (2010)] enjoys existence, uniqueness, and regularity of the prefactor. Furthermore, we present numerical results of the dynamical equation that describes to leading order the nonlocal regime of the Kelvin-Wave dynamics. We compare our findings with the analytical results from the proposed local and nonlocal theories for Kelvin-Wave dynamics and show an agreement with the nonlocal predictions. Accordingly, the spectrum proposed by L’vov and Nazarenko should be used in future theories of quantum turbulence. Finally, for weaker Wave forcing we observe an intermittent behavior of the Wave spectrum with a fluctuating dissipative scale, which we interpreted as a finite-size effect characteristic of mesoscopic Wave turbulence.
Masatomo Fujiwara - One of the best experts on this subject based on the ideXlab platform.
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role of the equatorial Kelvin Wave in stratosphere troposphere exchange in a general circulation model
Journal of Geophysical Research, 2001Co-Authors: Masatomo Fujiwara, Masaaki TakahashiAbstract:Large-scale disturbances which cause the variations of ozone and water around the equatorial tropopause are investigated with a general circulation model incorporating a simplified ozone photochemistry, realistic topography, and seasonal cycle of the sea surface temperature. Eastward moving large-scale equatorial gravity Waves are found to be dominant to modulate the minor constituents' distribution around the equatorial tropopause. A case over the Indian Ocean in the northern summer was investigated in detail. The disturbance had the characteristics of the equatorial Kelvin Wave at the tropopause level, coupled with organized active convections in the troposphere. Associated with the downward displacement (and suppressed-convection) phase of this system, dry, ozone-rich stratospheric air moved downward into the upper troposphere. At the opposite phase, physical and dynamical processes above the organized active convections prevented the lower stratosphere from accumulating excess water. Thus the dryness around the equatorial tropopause is maintained during the passage of such a system. Analysis of 4-year integration data reveals that such disturbances are especially active over the Indian Ocean during the northern summer through autumn. This is probably related to the development of the summer monsoon circulation over south Asia. This model has also simulated the zonal Wave one structure of tropical tropospheric ozone and suggested the important contribution of convective transport to the structure.
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stratosphere troposphere exchange of ozone associated with the equatorial Kelvin Wave as observed with ozonesondes and rawinsondes
Journal of Geophysical Research, 1998Co-Authors: Masatomo Fujiwara, Kazuyuki Kita, Toshihiro OgawaAbstract:An intensive observation with ozonesondes and rawinsondes was conducted in Indonesia in May and June 1995 to investigate a phenomenon of ozone enhancement in the tropical upper troposphere. We obtained the characteristics of an enhancement that continued for about 20 days, concurring with a zonal wind oscillation associated with the equatorial Kelvin Wave around the tropopause and the Madden-Julian oscillation (MJO) in the troposphere. The isoline of ozone mixing ratio of 40 nmol/mol moved by 5.0 km downward from 17.8 km to 12.8 km, while the tropopause height was 16.2-17.8 km throughout the period. Moreover, the maximum ozone concentration of 300 nmol/mol at the tropopause was concurrent with the maximum eastward wind phase of the Kelvin Wave. The detailed mechanism of the ozone transport is interpreted as follows: The downward motion associated with the Kelvin Wave and the MJO transported the stratospheric ozone into the troposphere, and the air mixing due to the Kelvin Wave breaking at the tropopause also caused stratosphere-troposphere exchange. The upper limit of the net amount of ozone transported from the stratosphere was estimated to be 9.9 Dobson units with the zonal and meridional extents of the ozone-increased region of more than 6.6 × 10 6 m and 1.8 × 10 6 m, respectively, to imply the potential to affect the photochemistry around the tropical tropopause.
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Stratosphere‐troposphere exchange of ozone associated with the equatorial Kelvin Wave as observed with ozonesondes and rawinsondes
Journal of Geophysical Research: Atmospheres, 1998Co-Authors: Masatomo Fujiwara, Kazuyuki Kita, Toshihiro OgawaAbstract:An intensive observation with ozonesondes and rawinsondes was conducted in Indonesia in May and June 1995 to investigate a phenomenon of ozone enhancement in the tropical upper troposphere. We obtained the characteristics of an enhancement that continued for about 20 days, concurring with a zonal wind oscillation associated with the equatorial Kelvin Wave around the tropopause and the Madden-Julian oscillation (MJO) in the troposphere. The isoline of ozone mixing ratio of 40 nmol/mol moved by 5.0 km downward from 17.8 km to 12.8 km, while the tropopause height was 16.2–17.8 km throughout the period. Moreover, the maximum ozone concentration of 300 nmol/mol at the tropopause was concurrent with the maximum eastward wind phase of the Kelvin Wave. The detailed mechanism of the ozone transport is interpreted as follows: The downward motion associated with the Kelvin Wave and the MJO transported the stratospheric ozone into the troposphere, and the air mixing due to the Kelvin Wave breaking at the tropopause also caused stratosphere-troposphere exchange. The upper limit of the net amount of ozone transported from the stratosphere was estimated to be 9.9 Dobson units with the zonal and meridional extents of the ozone-increased region of more than 6.6×106 m and 1.8×106 m, respectively, to imply the potential to affect the photochemistry around the tropical tropopause
